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On-Line NDE for Control and Modeling of Ceramic Processing

Published online by Cambridge University Press:  29 November 2013

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The high-temperature structural properties of ceramics make them unique candidates for application in such systems as advanced gas turbines and other heat engines. Of concern, however, is the variability in fast fracture strength of structural ceramics which is due, in part, to the sensitivity of ceramics to very small (e.g., 20–50 μm) critical flaws and the difficulty in detecting and characterizing this type of flaw by nondestructive examination (NDE) techniques.

The flaw sensitivity of ceramics and the typically wide variation in flaw sizes result in the situation illustrated in Figure 1, which is a frequency distribution of fast fracture strengths for a hypothetical structural ceramic with characteristic strength of 350 MPa and Weibull modulus of 5. The strength requirement, 250 MPa, for a particular application is shown. In this illustration, a significant fraction of the population of ceramic parts, 17%, has a strength below the 250 MPa requirement.

The situation illustrated in Figure 1 is typical of structural ceramics today: although in many cases the average properties of a specific ceramic may be suitable for the intended use, a significant fraction of the parts made of that material will be unsuitable. The unacceptable parts are, of course, very difficult to distinguish from the rest of the population.

Type
On-Line Nondestructive Evaluation
Copyright
Copyright © Materials Research Society 1988

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References

1.Weibull, W., “A Statistical Distribution Function of Wide Applicability,” J. Appl. Mech. 18(3) (1951) p. 293297.CrossRefGoogle Scholar
2.Weibull, W., “A Static Theory of the Strength of Materials,” Ing. Vetenskaps Akad. Handl. 151 (1939).Google Scholar
3.Deming, W.E., Quality, Productivity, and Competitive Position, Center for Advanced Engineering Study (Massachusetts Institute of Technology, Cambridge, 1982).Google Scholar
4.Johnson, D.R., McClung, R.W., Janney, M.A., and Hanusiak, W.M., Needs Assessment for Nondestructive Testing and Materials Characterization for Improved Reliability in Structural Ceramics for Heat Engines, ORNL/TM-10354 (Oak Ridge National Laboratory, Oak Ridge, TN, August 1987).CrossRefGoogle Scholar
5.Natansohn, S., “Nondestructive Evaluation of Powders for Advanced Ceramics,” Proceedings of Conference on Nondestructive Testing of High-Performance Ceramics, August 25-27, 1987, Boston (American Ceramic Society, Westerville, OH, 1987).Google Scholar
6.Bowen, H.K., “Research Needs: Ceramic Processing,” Workshop on Ceramics, Gas Research Institute, Gas Research Institute, April 21-22, 1983, Chicago, IL.Google Scholar
7.Kupperman, D.S.et al., Applications of NDE Methods to Green Ceramics: Initial Results, ANL/FE-83-25, Argonne National Laboratory, Argonne, IL, 1984.CrossRefGoogle Scholar
8.Corbin, N.D., Pujari, V.K., Antal, J.J., and Marotta, A.S., “NDE of Structural Ceramics Using Neutron Radiography,” Proceedings of Conference on Nondestructive Testing of High-Performance Ceramics, August 25-27, 1987, Boston (American Ceramic Society, Westerville, OH, 1987).Google Scholar
9.Kupperman, D., private communication.Google Scholar
10.Ackerman, J.L., Garrido, L., Ellingson, W.A., and Weyand, J.D., “The Use of NMR Imaging to Measure Porosity and Binder Distributions in Green-State and Partially Sintered Ceramics,” Proceedings of Conference on Nondestructive Testing of High-Performance Ceramics, August 25-27, 1987, Boston (American Ceramic Society, Westerville, OH, 1987).Google Scholar
11.Welsh, L.B., Gonczy, S.T., Dworkin, J., and Giambaivo, A., “Optimization of Proton NMR Imaging for the Analysis of Green-State Ceramics,” Proceedings of Conference on Nondestructive Testing of High-Performance Ceramics, August 25-27, 1987, Boston (American Ceramic Society, Westerville, OH, 1987).Google Scholar
12.Koenigsberg, W. and Neil, J.T., “Ceramic Binder Removal Studies Using Projection Radiography,” Proceedings of Conference on Nondestructive Testing of High-Performance Ceramics, August 25-27, 1987, Boston (American Ceramic Society, Westerville, OH, 1987).Google Scholar
13.Jones, M.P. and Blessing, G.V., “Real-Time Ultrasonic Nondestructive Evaluation of Green State Ceramic Powders During Compaction,” Nondestructive Testing Communications, Vol. 2 (Gordon and Breach, 1986) p. 155168.Google Scholar
14.Jones, M.P. and Blessing, G.V., “Ultrasonic Evaluation of Spray-Dried Ceramic Powders During Compaction,” Proceedings of Second International Symposium on the Nondestructive Characterization of Materials, Montreal, July 21-23, 1986 (Plenum Press, New York, NY, 1987).Google Scholar
15.Jones, M.P. and Blessing, G.V., “Ultrasonic Evaluation of Spray-Dried Alumina Powder During and After Compaction,” Proceedings of Conference on Nondestructive Testing of High-Performance Ceramics, August 25-27, 1987, Boston (to be published).CrossRefGoogle Scholar
16.McClung, R.W., “Nondestructive Testing of Nuclear Ceramic Materials,” Am. Ceram. Soc. Bull. 49(9) (1970) p. 777781.Google Scholar
17.McClung, R.W., “Studies in Contact Microradiography,” Mater. Res. Std. 4(2) (1964) p. 6669.Google Scholar
18.Friedman, W.D., Harris, R.D., Engler, P., Hunt, P.K., and Srinivasan, M., “Characterization of Green Ceramics with X-Ray Tomography and Ultrasonics,” Proceedings of Conference on Nondestructive Testing of High-Performance Ceramics, August 25-27, 1987, Boston (American Ceramic Society, Westerville, OH, 1987).Google Scholar
19.Baaklini, G.Y. and Roth, D.J., Probability of Detection of Internal Voids in Structural Ceramics Using Microfocus Radiography, NASA Technical Memorandum 87164, (NASA Lewis Research Center, Cleveland, OH, November 1985).CrossRefGoogle Scholar
20.Roberts, R.A., Ellingson, W.A., and Vannier, M.W., “A Comparison of X-Ray Computed Tomography, Through-Transmission Ultrasound, and Low kV X-Ray Imaging for Characterizing Green State Ceramics,” presented at the 15th Symposium on Nondestructive Evaluation, San Antonio, TX, April 23-25, 1985, Southwest Research Institute (to be published).Google Scholar
21.Jones, M.P., Blessing, G.V., and Robbins, C.R., “Dry-Coupled Ultrasonic Elasticity of Sintered Ceramics and Their Green States,” Mater. Eval. 44(6) (June 1986) p. 859862.Google Scholar
22.Hardman-Rhyne, K., Fuller, E.R. Jr., and Tighe, N.J., “Nondestructive Characterization of Distributed Damage,” 1984 Technical Activities, NBSIR84-2944, (National Bureau of Standards, Gaithersburg, MD, 1984) p. 116124.Google Scholar
23.Ackerman, J.L., Ellingson, W.A., Koutcher, J.A., and Rosen, B.R., “Development of Nuclear Magnetic Resonance Imaging Techniques for Characterizing Green-State Ceramic Materials,” Proceedings of Second International Symposium on the Nondestructive Characterization of Materials, Montreal, July 2123, 1986 (Plenum Press, New York, NY, 1987).Google Scholar